This article originally appeared on ABACUS If your new iPhone feels unusually slow, it might not be your imagination. Foxconn workers in mainland China were found selling defective iPhone parts for more than two years to a Taiwan business, which used them to assemble new phones for sale, according to a report by Taiwanese Mirror Media. The report quoted an insider that said that the iPhone components were set aside for destruction, but they wound up being resold by employees at Foxconn’s factory in Zhengzhou, allegedly raking in US$43 million. Factory production lines inevitably have some defective components, usually ranging from 3 to 5 percent, the report said. The affected phones include iPhone 8 and iPhone X series, according to the source. The ruse reportedly cost Apple an estimated US$3 billion a year with Mirror Media publishing an alleged letter from the Cupertino-based company saying that they launched an investigation. Foxconn also launched its own investigation on Wednesday, Taiwan News reported . Foxconn told Abacus in a statement that as a matter of company policy, it doesn’t comment on any aspect of work for any customer. However, it did say the company has a strict code of conduct and that it won’t hesitate to act against violations. Apple did not respond to requests for comment. For more insights into China tech, sign up for our tech newsletters , subscribe to our award-winning Inside China Tech podcast , and download the comprehensive 2019 China Internet Report . Also roam China Tech City , an award-winning interactive digital map at our sister site Abacus .